Driving device for driving bolts or other drivepins into fixed structural or building elements or the like

ABSTRACT

A device for driving bolts or studs into structural elements comprises a tubular housing having a closed upper end and an open lower end. A socket fixed in the upper end of the housing includes a passage and a firing chamber communicating therewith. A firing pin axially slidable in the passage can be selectively projected by means of a rotatable pushbutton shank, interposed between the upper end of the housing and the socket, which has a plurality of circumferential recesses of different depths each arranged to engage the head of the firing pin to extend the lower end of that pin into the chamber. A barrel longitudinally movable in the housing against a spring force surrounds a piston carrying a cartridge which upon engagement by the firing pin, in response to a hammer blow upon the top of the housing, is detonated to thrust the piston outwardly together with a driving pin seated in the lower end of the barrel; the intensity of the thrust depends on the selected recess engaging the firing pin.

Uted States Patent Schneider DRIVING DEVICE FOR DRIVING BOLTS OR OTHER DRIVEPINS INTO FIXED STRUCTURAL OR BUILDING ELEMENTS OR THE LIKE Inventor: Fritz Schneider, Burgb'emheim,

Germany Assignee: Impex-Essen GmbH, Ahsbach, Ger

many

Filed: Oct. 5, 1970 Appl. No.: 77,898

Foreign Application Priority Data Oct. 10,1969 Germany ..P 19 51 121.8

US. Cl. ..227/1o Int. Cl "1325c 1/14 Field of Search .Q. ..'.....22'7/8, 10, 11

References Cited '1' IIIIIIIIIZI 3,563,439 2/1971 Pomeroy ..227/10 Primary Examiner-Granville Y. Custer, Jr.

Attorney-Karl F. Ross [57] ABSTRACT A device for driving bolts or studs into structural elements comprises a tubular housing having a closed upper end and an open lower end. A socket fixed in the upper end of the housing includes a passage and a firing chamber communicating therewith. A firing pin axially slidable in the passage can be selectively projected by means of a rotatable pushbutton shank, interposed between the upper end of the housing and the socket, which has a plurality of circumferential recesses of different depths each arranged to engage the head of the firing pin to extend the lower end of that pin into the chamber. A barrel longitudinally movable in the housing against a spring force surrounds a piston carrying a cartridge which upon engagement by the firing pin, in response to a hammer blow upon the top of the housing, is detonated to thrust the piston outwardly together with a driving pin seated in the lower end of the barrel; the intensity of the thrust depends on the selected recess engaging the firing pin.

10 Claims, 7 Drawing Figures PATENTEB 3718.271 sumlurs' FRITZ SCHNEIDER PATENTED BZ 7 975 SHEET 3 BF 6 Fi s lnvenfor:

PATENTEDFEBZYIW 3.718.271

SHEET I; 0F 6 f 0 Q5) QCQ Q1 ,9; 4

DRIVING DEVICE FOR DRIVING BOLTS OR OTHER DRIVEPINS INTO FIXED STRUCTURAL OR BUILDING ELEMENTS OR THE LIKE My present invention relates to a device for driving bolts or studs into fixed structural or building elements or the like, the device being provided with a piston which is driven by the gas pressure of a cartridge and acts on the stud to be driven, the shaft of the piston being moved in a barrel which is longitudinally displaceable in a housing of the device, as by being slidable therein against the force of a recoil spring. Upon the lodging of a stud in the barrel in the insertion position, the rear end of the piston is receivable in a firing chamber formed by a socket which is provided with a firing pin positioned so as to be axially displaceable therein to a limited extent for setting off a cartridge carried for example on the rearward end of the piston.

With known bolt-driving devices of the aforementioned kind, owing to the longitudinal displaceability or adjustability of the barrel even where the location of the cartridge is fixed, bolts of various lengths can be driven, for which purpose the barrel can be screwed and/or pushed into the housing to a greater or lesser extent according to the selected length of the bolt which is inserted head first into the barrel; this bolt urges the abutting thrust piston back until the cartridge-carrying rear end thereof which contains the cartridge enters the firing chamber. As the socket provides only for a comparatively short driving stroke, i.e., the gases produced by combustion of the powder charge in the firing chamber act only over a comparatively short axial distance on the thrust piston to be moved in order that they may quickly expand or escape at the sides, only a minor powder residue is left in the firing chamber, whereby the operation and servicing of such driving devices is simplified. In a known driving device of the type in question, the socket together with its longitudinally displaceable firing pin is mounted in a separate breech ring in the housing and are provided with means for clamping, securing and cocking the firing pin which is released by a finger-operated trigger. This still requires a rather complicated construction. Moreover, with these devices, any alteration of the drive force or capacity which becomes necessary can be achieved only by using appropriately adjusted cartridge loadings or thrust pistons. Furthermore, with these devices, there is only a limited protection against accidental firing because, with the barrel pushed back and with the firing pin cocked through inadvertent actuation release of the firing mechanism may produce an impact sufficient to set off the cartridge.

The object of my invention is to provide an improved driving device of the aforestated type which is free from the faults described but retains its inherent advantages, has moreover a simplified construction, is fired by the impact of a hand-held hammer, and furthermore permits ready adjustment of its driving capacity while being completely secured against inadvertent firing 'despite the use of the same type of cartridge.

In accordance with my present invention, the firing pin confronting the thrust piston co-operates with a manually operable control member serving as an adjustable backstop for that pin, this control member being selectively movable into any of several different operating positions for varying the extent of penetration of the pin into the firing chamber. By this means it is possible to modify the ejective force exerted by the piston upon detonation of the charge received between the firing pin and an inner extremity of the piston inserted into the firing chamber.

According to a more specific feature of my invention, the control member is rotatively lodged in a transverse bore of the housing so as to be withdrawable from engagement with the firing pin whereby the latter becomes ineffectually movable in its socket. Advantageously, the control member is in the shape of a pushbutton urged into its disengaged position by a biasing spring so as to extend laterally outwardly from the housing unless manually depressed into a position of engagement with the firing pin. Several peripheral recesses on the generally cylindrical shank of the control member, differing in depth among one another, respectively receive an end of the firing pin in the several operating positions of that member which may be indexed in any of these positions by a spring-loaded ball engageable with any of several axially extending peripheral grooves on the shank. Thus, the rotary position of the pushbutton is maintained even upon its disengagement from the firing pin.

The necessary relative motion between the socket and the barrel, designated to insert the inner extremity of the piston into the firing chamber after a bolt or stud has been introduced into the muzzle end of the barrel, is preferably brought about by making the barrel slidable in the open end of the tubular housing. Thus, pressure exerted against the force of a restoring spring upon the opposite, closed end of the housing, while the barrel is held against a structure in which the stud is to be emplaced, sandwiches the charge between the pin and the piston so that the charge can be detonated by a sharp blow on that closed end.

According to another advantageous feature of my invention, the barrel in its fully extended position is releasable from its normal alignment with the firing pin and can be tilted so that the inner extremity of the thrust piston becomes accessible through a lateral opening. This feature enables rapid loading of the device by the insertion of a powder pellet, representing the charge to be detonated, into a recess in that inner piston extremity which consequently confronts the firing pin.

The invention will now be further described with reference to the accompanying drawing in which a driving device embodying the invention is illustrated in axial longitudinal sectional view and in various operating positions, to wit:

FIG. 1 shows the device in the charged condition in its normal starting position;

FIG. 2 is a view similar to FIG. 1 but taken at right angles thereto;

FIG. 3 shows the device in its cocked state and set for a high-power driving;

FIG. 4 shows the firing position corresponding to FIG. 3 but with a somewhat reduced driving power;

FIG. 5 shows the device in the loaded position with the barrel let down;

FIG. 6 shows the device in a possible impact position on being accidentally dropped; and

FIG. 7 is a cross-sectional view taken on the line VIIVII of FIG. 1.

The illustrated driving device as shown in FIG. 1 essentially comprises a tubular housing 2, provided with a handle 1 and a socket 3 tightly screwed into same, a firing pin 4 limitedly axially displaceable in the socket, and a barrel 8 which is axially displaceable in the housing 2. A thrust piston 9 is longitudinally displaceable within the barrel 8 in which is received a bolt o'r stud 10 which is to be driven into a structural building element or other object. A recoil spring 11 in the housing 2 acts by way of a ring 12 on the barrel 8 to urge the latter to its extended position, which corresponds to the initial position of the device illustrated in FIG. 1. An explosive charge in the form of a pellet 13, which acts as a cartridge, is inserted in a suitable recess at the inwardly projecting rear extremity of the piston 9.

The firing pin 4, which is provided with a thickened head 4 and an annular groove 4" which reduces the risk of erosion, is displaceably received in a stepped bore 3' of the socket 3, a shoulder 3" of the bore serving to limit the outward movement of the pin. The latter is limited as regards its rearward displacement and firing positions by a pushbutton-type control member 5 which is rotatable and axially displaceable in a cross-bore 14 in the housing 2. The member 5 is provided on its perimeter, for co-operation with the head 4' of the firing pin 4, with differently sized recesses 5', 5", 5" which correspond in number to the various firing positions, as shown most clearly in FIG. 2. The control member 5 is also provided with a longitudinal bore 5" having a compression spring 15 located therein. A guiding locking pin 6 which is secured to the housing 2 to extend coaxially of the cross-bore 14 projects into the longitudinal bore 5 of the pushbuttons shank. The spring 15 tends to keep the control member 5 in an outwardly projecting safety position in which a shoulder thereof abuts an internally projecting annular edge of a screw socket 16 to act as a stop. As shown in FIG. 2, the control member 5 is in addition provided with several indexing grooves 5" which are angularly spaced in correspondance with the recesses 5', 5", 5" and which interact with a detent ball 18 which is resiliently supported in a bore 17 in the housing 2 so that the control member can be releasably held in its various angular adjustment positions both when engaged and disengaged.

The barrel 8, which is longitudinally displaceable in the housing 2 against the action of the recoil spring 11,

is rotatably connected in its offset position illustrated in FIG. 1 with the housing by means of a bayonet or slide lock. After unlocking, the barrel 8 may be brought into its fully extended position and then laterally tilted into a loading position through a pair of diametrically opposite openings 19, 20 in the front end of the housing as shown in FIG. 5. The slide lock consists essentially of two locking segments 21 arranged opposite each other at the front end of the housing 2 and integral therewith between the openings 19, 20, each segment having an upper transverse shoulder 21' co-operating with bayonet lugs 8 projecting radially from the inner end of the barrel 8. In the normal position of the device, as seen in FIGS. 2 and 7, the lugs 8' rest on the shoulders 21 of the locking segments 21. If, however, the barrel 8 is brought out of its locked position by rotation through 90 and slid axially within the housing 2 into its outermost position and is subsequently tilted as shown in FIG. 5, then the ring 12 comes to rest on the shoulders 21 of the locking segments 21. These shoulders 21' are so located within the housing that the recoil spring 11 engaging the ring 12 remains stressed even when the device is in the loading position of FIG. 5. The opening 20 in the front end of the housing 2 is designed as an inclined bore whose diameter corresponds to the largest diameter, or the largest transverse dimension, of the barrel 8 so that the latter can be inserted into or removed from the housing 2 through this bore 20. A stop pin 7 which is detachably secured in the housing 2 passes through the front end of the inclined bore or opening 20, the barrel 8 engaging the pin 7 in the tilted position (see FIG. 5) by one of its lugs 8' coming to rest on the lower edge of this bore.

With the barrel 8 in the loading or tilted position illustrated in FIG. 5, the pellet 13 of explosive powde'r can be easily inserted into the corresponding recess in the rearward end of the piston 9. After that, the barrel 8 is dropped down around the stop pin 7 and pushed up into the housing 2 until it can be rotated by about the axis of the housing so that its bayonet lugs 8 can pass behind the locking segments 21 in the housing and rest on the shoulders 21 The stud 10, which is provided at its tip with a guiding or holding capsule 10', is then inserted into the barrel 8 against the weight of the thrust piston 9. The device is now in its starting position illustrated in FIG. 1 and 2. At this point, or even before, the desired driving force can be selected at the control member 5 by suitable rotary adjustment thereof. Since the control member 5 is at first still located in its outwardly extending safety position, the pellet 13 cannot be fired even if the device is dropped since when the apparatus hits the ground 22, for example as shown in FIG. 6, the firing pin 4 is simply pushed up to its rearward end position against the guiding pin 6 and thus no longer projects into the firing chamber 3" of the socket 3.

The device can be held in one hand by the handle 1 and set or thrust into the driving position in which the piston 9 is pushed by the bolt or stud 10 into the chamber 3" and the barrel 8 is at the same time pushed back by the length of the inserted stud 10 into the housing 2. The control member 5 is thereupon pressed in by movement of the fingers of the hand holding the device, which is then fired by the blow of a hammer, held in the other hand, on the rear end face 23 of the housing.

With the pushbutton 5 in the rotary-adjustment position illustrated in FIG. 3, the device is set for the maximum driving force or capacity since the firing pin 4 here projects with its front firing surface only a little way into the chamber 3" so that the gases which are formed here on explosion of the pellet 13 meet with the smallest possible expansion space and can subject the piston 9 to the longest possible preliminary path out of the firing chamber 3. In the position of FIG. 4, the device is set to the smallest driving capacity since here the firing pin 4, maintained in its firing position by the control member 5, projects comparatively far into the chamber 3" so that the combustion gases meet with a relatively large expansion space and consequently subject the thrust piston 9 to a correspondingly shorter preliminary path.

After ejection of the stud 10 and removal of the device from the driving position, the barrel 8 returns again under the effect of the recoil spring 11 into its initial position illustrated in FIGS. 1 and 2, from where it can be brought into its loading or tilted position illustrated in FIG. 5 by rotation through 90 and further withdrawal from the housing 2.

What we claim is:

l A driving device for the emplacement of studs and the like in a structure, comprising:

a tubular housing provided at one end with a barrel adapted to receive a stud to be driven;

a thrust piston slidable in said barrel for ejecting said stud; socket in said housing near the opposite end thereof forming a firing chamber open toward an inner extremity of said piston, said socket and said piston being relatively movable toward each other by axial pressure upon said opposite end, with said barrel held against a structure, for introduction of said extremity into said chamber preparatorily to detonation of a charge therein;

a firing pin slidable in said socket and aligned with said piston for detonating said charge, received between said firing pin and said extremity, in response to a sharp blow upon said opposite end; and

manually operable control means on said housing selectively movable into any of several different operating positions for backstopping said firing pin with varying penetration thereof into said chamber, thereby modifying the ejective force exerted by said piston upon detonation of said charge.

2. A device as defined in claim 1 wherein said control means comprises a rotary member lodged in said housing adjacent said socket for engagement with said firing pin.

3. A device as defined in claim 2 wherein said housing is provided with a transverse bore accommodating said rotary member, the latter being withdrawable in said bore from engagement with said firing pin for making same ineffectually movable in said socket.

4. A device as defined in claim 3, further comprising spring means bearing upon said member for urging same into a disengaged position.

5. A device as defined in claim 4 wherein said member projects laterally from said housing in said disengaged position for manual depression into a position of engagement with said firing pin.

6. A device as defined in claim 5 wherein said member has a generally cylindrical shank provided with several peripheral recesses of different radial depth respectively receiving an end of said firing pin in said several operating positions.

7. A device as defined in claim 6 wherein said shank is provided with a number of axially extending peripheral grooves corresponding to the number of said recesses, further comprising indexing means engageable with any of said grooves for releasably holding said member in a selected operaing position while permitting axial displacement thereof between said disengagement position and said position of engagement.

8. A device as defined in claim 3 wherein said barrel slidably projects from said one end of said housing and said socket is fixedly mounted at said opposite end thereof, further comprisin resilient means in said housing bearing upon said arrel for urging same into an extended position remote from said socket.

9. A device as defined in claim 8 wherein said housing is provided at said one end with an opening, said barrel in its extended position being tiltable in said one end out of line with said socket for making said extremity accessible through said opening, said extremity being provided with a recess for receiving an explosive pellet constituting said charge.

10. A device as defined in claim 9 wherein said barrel is provided with bayonet lugs normally engaging a pair of segmental shoulders in said one end, said opening being provided with an edge forming a rest for one of said bayonet lugs in the tilted position of said barrel. 

1. A driving device for the emplacement of studs and the like in a structure, comprising: a tubular housing provided at one end with a barrel adapted to receive a stud to be driven; a thrust piston slidable in said barrel for ejecting said stud; a socket in said housing near the opposite end thereof forming a firing chamber open toward an inner extremity of said piston, said socket and said piston being relatively movable toward each other by aXial pressure upon said opposite end, with said barrel held against a structure, for introduction of said extremity into said chamber preparatorily to detonation of a charge therein; a firing pin slidable in said socket and aligned with said piston for detonating said charge, received between said firing pin and said extremity, in response to a sharp blow upon said opposite end; and manually operable control means on said housing selectively movable into any of several different operating positions for backstopping said firing pin with varying penetration thereof into said chamber, thereby modifying the ejective force exerted by said piston upon detonation of said charge.
 2. A device as defined in claim 1 wherein said control means comprises a rotary member lodged in said housing adjacent said socket for engagement with said firing pin.
 3. A device as defined in claim 2 wherein said housing is provided with a transverse bore accommodating said rotary member, the latter being withdrawable in said bore from engagement with said firing pin for making same ineffectually movable in said socket.
 4. A device as defined in claim 3, further comprising spring means bearing upon said member for urging same into a disengaged position.
 5. A device as defined in claim 4 wherein said member projects laterally from said housing in said disengaged position for manual depression into a position of engagement with said firing pin.
 6. A device as defined in claim 5 wherein said member has a generally cylindrical shank provided with several peripheral recesses of different radial depth respectively receiving an end of said firing pin in said several operating positions.
 7. A device as defined in claim 6 wherein said shank is provided with a number of axially extending peripheral grooves corresponding to the number of said recesses, further comprising indexing means engageable with any of said grooves for releasably holding said member in a selected operaing position while permitting axial displacement thereof between said disengagement position and said position of engagement.
 8. A device as defined in claim 3 wherein said barrel slidably projects from said one end of said housing and said socket is fixedly mounted at said opposite end thereof, further comprising resilient means in said housing bearing upon said barrel for urging same into an extended position remote from said socket.
 9. A device as defined in claim 8 wherein said housing is provided at said one end with an opening, said barrel in its extended position being tiltable in said one end out of line with said socket for making said extremity accessible through said opening, said extremity being provided with a recess for receiving an explosive pellet constituting said charge.
 10. A device as defined in claim 9 wherein said barrel is provided with bayonet lugs normally engaging a pair of segmental shoulders in said one end, said opening being provided with an edge forming a rest for one of said bayonet lugs in the tilted position of said barrel. 